diff -dur boost_1_43_0.orig/libs/program_options/src/options_description.cpp boost_1_43_0/libs/program_options/src/options_description.cpp
--- boost_1_43_0.orig/libs/program_options/src/options_description.cpp	2010-01-08 22:00:57.000000000 +0100
+++ boost_1_43_0/libs/program_options/src/options_description.cpp	2010-06-22 14:28:56.115538359 +0200
@@ -305,7 +305,8 @@
                                       bool long_ignore_case,
                                       bool short_ignore_case) const
     {
-        shared_ptr<option_description> found;
+        shared_ptr<option_description> found_approx;
+        shared_ptr<option_description> found_full;
         vector<string> approximate_matches;
         vector<string> full_matches;
         
@@ -323,15 +324,15 @@
             if (r == option_description::full_match)
             {                
                 full_matches.push_back(m_options[i]->key(name));
+                found_full = m_options[i];
             } 
             else 
             {                        
                 // FIXME: the use of 'key' here might not
                 // be the best approach.
                 approximate_matches.push_back(m_options[i]->key(name));
+                found_approx = m_options[i];
             }
-
-            found = m_options[i];
         }
         if (full_matches.size() > 1) 
             boost::throw_exception(
@@ -346,7 +347,9 @@
             boost::throw_exception(
                 ambiguous_option(name, approximate_matches));
 
-        return found.get();
+        if (!full_matches.empty())
+            return found_full.get();
+        return found_approx.get();
     }
 
     BOOST_PROGRAM_OPTIONS_DECL